The present invention relates to devices for facilitating the insertion or extraction of printed circuit boards or cards in connector-contact applications. Specifically, the present invention relates to an inserter/ejector having improved board mounting and alignment features.
The growing complexity of computer systems, e.g., in servers for telecommunications, requires the utilization of many interconnected components. A common way to interconnect the components is by usage of a number of printed circuit boards (PCBs), a number of which may be compactly housed in a computer chassis. With miniaturization, however, the numbers of components and PCBs within a given system increase as the amount of space decreases. It then becomes a problem to access components on a given PCB within an array of such circuit boards. For various reasons, e.g., narrow spacing, heat, and sensitivity of the components, removal of the given PCB is a delicate task.
Current techniques for removing PCBs employ the use of various lever-type devices which couple to the PCB or card by way of mounting pins affixed to the board. As noted, these lever-type devices are implemented for the insertion or extraction of PCBs into environments in which many such boards are located in close proximity, e.g., in large mainframe computers, servers or other high capacity computing systems. In such environments, it is often difficult, if not impossible, to reach between the respective boards so that one may be inserted or removed without damaging others.
An example of a conventional inserter/extractor, e.g., such as described in U.S. Pat. No. 4,975,073 issued to Weisman, is illustrated in FIG. 1, and generally designated therein by the reference numeral 100. As shown in the figure, the inserter/extractor 100 attaches to a PCB board 120 by two stainless steel pins, e.g., an upper pin 105 and a lower pin 110, mounted through respective openings 115A and 115B drilled though the board 120. In use, an opening 125 in a lower portion 130 of the inserter/extractor device 100 is fitted over the lower pin 110, about which the entire device 100 pivots.
With reference now to FIG. 2, there is illustrated a U-channel, generally designated by the reference numeral 200, at an end 205 of PCB 220 that is perpendicular to the particular connections or slots in which the PCBs are to be installed, and which may be used to provide an actuating surface. It should be understood that the U-channel is generally part of the host system chassis housing the PCB 220. With reference also to FIG. 1, as device 100 rotates about the lower pin 110, a cutout 135 in the lower portion 130 of the device 100 makes contact with the U-channel 200 and acts as a lever to facilitate insertion or extraction of the PCB 120 with relative ease. When not in use, the device 100 may be locked against the edge of the PCB 120 by clamping an upper portion 140 thereof about the upper pin 105 mounted through the board 120. It should be understood that a spring-loaded joint 150, employed between the upper 140 and lower 130 portions of the device 100, is similar to a spring-loaded joint found in a common clothes pin.
Such conventional devices may also be found in simpler ejector-only type forms which resemble a simplified lower portion of the device described above, i.e., lower portion 130 of device 100, and which are limited in use to extracting PCBs or cards 120 that have been previously installed.
While the aforementioned devices have been somewhat useful, these conventional inserter/extractors require pre-installation of one or more of the aforedescribed pins through the PCB, i.e., pins 105 and 110, lack a self aligning mechanism to assure proper alignment of the PCB upon insertion, and provide minimal space for labeling the board onto which the devices are attached. Accordingly, there is a need for an improved PCB inserter/ejector which installs with minimal hardware, has a self aligning mechanism for positive board location, and has a relatively large area for labeling.
In a preferred embodiment, the inserter/ejector of the present invention includes a body and a lever arm. The body is designed with a lip and has a flexible design to snap fit into a mounting panel, whereby a PCB is mounted thereto without the need of screws, pins or rods which must be pre-installed on the PCB as with conventional designs. The lever arm is pivotally attached to the body by a pair of hinge pins, and may be secured in a locked or fully inserted position by a locking mechanism portion of the body. The lever arm is provided with a cutout for actuating a U-channel and creating a lever action capable of providing significant force for the insertion or removal of an attached PCB. The lever arm also features a relatively large inset label area for clearly labeling the attached PCB. The improved inserter/ejector of the present invention further implements a guide pin for positive location or alignment of the PCB with a host system prior to insertion.